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Asymmetric Dearomatization of Phthalazines by Anion-Binding Catalysis.

ABSTRACT: A straightforward methodology for the enantioselective synthesis of 1,2-dihydrophthalazines via dearomatization of phthalazines by anion-binding catalysis has been developed. The process involves the Mannich-type addition of silyl ketene acetals to in situ generated N-acylphthalazinium chlorides using a tert-leucine derived thiourea as a H-bond donor catalyst. Ensuing selective and high-yielding transformations provide appealing dihydro- and tetrahydro-phthalazines, phthalazones, and piperazic acid homologues, en route to biologically relevant molecules.

SUBMITTER: Velazquez M

PROVIDER: S-EPMC10729020 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Asymmetric Dearomatization of Phthalazines by Anion-Binding Catalysis.

Velázquez Marta M Fernández Rosario R Lassaletta José M JM Monge David D

Organic letters 20231201 49

A straightforward methodology for the enantioselective synthesis of 1,2-dihydrophthalazines via dearomatization of phthalazines by anion-binding catalysis has been developed. The process involves the Mannich-type addition of silyl ketene acetals to in situ generated N-acylphthalazinium chlorides using a tert-leucine derived thiourea as a H-bond donor catalyst. Ensuing selective and high-yielding transformations provide appealing dihydro- and tetrahydro-phthalazines, p ...[more]

PMID: 38039188

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